821621000126128 has 40 divisors (see below), whose sum is σ = 1626356005125120. Its totient is φ = 401922625715520.

The previous prime is 821621000126093. The next prime is 821621000126149.

821621000126128 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×821621000126128² (a number of 31 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 197979448 + ... + 202086871.

It is an arithmetic number, because the mean of its divisors is an integer number (40658900128128).

Almost surely, 2^{821621000126128} is an apocalyptic number.

It is an amenable number.

821621000126128 is a deficient number, since it is larger than the sum of its proper divisors (804735004998992).

821621000126128 is a wasteful number, since it uses less digits than its factorization.

821621000126128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400069105 (or 400069099 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 40.

It can be divided in two parts, 821621000 and 126128, that added together give a palindrome (821747128).

The spelling of 821621000126128 in words is "eight hundred twenty-one trillion, six hundred twenty-one billion, one hundred twenty-six thousand, one hundred twenty-eight".